Now, this question pertains to the CMU MSCF program. I can't speak on their behalf or pretend to know what is the "right" answer to this question.
That said, I have to disclose that I do keep in touch with administrators at several top programs so while I know the general thinking, my advice should be taken as general guide, not specific to any program.
Remember this is an interview question and you should be able to answer follow up question. Once you start saying "I want to do X in 5 years then do Y to become Z", you need a clear and convincing answer for "How?" and "Why?", "What's your plan B?"
If you haven't thought about "How" and "Why", "Plan B" you clearly didn't think this through and it puts the onus back on you.
Every "I want to be a trader" wannabe will be asked that question. Do you know the percentage of that program's graduates become a traders right out of school? 5 years after graduation? How about for someone with similar background?
Do you know the average life shelf for a Wall Street trader? Do you know most traders are losing money? Do you know what it takes to open a hedge fund?
If you have answers to these at the ready, go and get them. If not, rethink your plan. I can only tell you that the people who have been reading applications are very cynical and they can smell BS about 10 seconds into your essay.
There are many shady programs taking shallow applicants. Top programs have learned their lesson that just taking the geeks with perfect GRE won't do they much good in the long run. They want savvy customers, who have a realistic view of the market and can benefit the program.
